In general, an airbag apparatus for a vehicle is a safety device which deploys an airbag cushion at the time of a collision accident so as to mitigate impact, and prevents an occupant from being catapulted out of a vehicle body. The airbag apparatus may be classified into a driver airbag (DAB) and a passenger airbag (PAB) which protect occupants seated in front seats at the time of a head-on collision, and a side airbag (SAB) and a curtain airbag (CAB) which protect the sides of the occupants at the time of a broadside collision.
Regarding the passenger airbag among the airbag apparatuses, the very important point is that a problem with injury to the neck of the occupant needs to be improved by maintaining internal pressure after a collision with the occupant.
Particularly, it is necessary to pass the New Car Assessment Program (NCAP) Test in order to export vehicles to the North America, and a neck injury test is a test item with the highest importance in assessment of marketability of the passenger airbag according to the NCAP, and as a result, it is essential to improve a technology of reducing injury to the neck in this technical field.
As a related technology, Korean Patent Application Laid-Open No. 10-2013-0062521 discloses ‘Airbag Cushion for Reducing Injuries having Vent Control Means’.
According to the airbag cushion for reducing injuries having a vent control means, a point of time at which a vent hole is closed is adjusted using a horizontal tether.
However, the airbag cushion for reducing injuries having a vent control means has a problem in that the vent hole cannot be closed in a case in which the horizontal tether is not pressed.